Foam mattress having an adjustable mattress core for adjusting and customizing its firmness, assembling method and kit thereof

ABSTRACT

It is disclosed a foam mattress having an adjustable mattress core for adjusting and customizing its firmness. The foam mattress has a foam base having an upper surface defining a top recess; and a plurality of foam inserts each configured to be disposed and assembled into the top recess to fill the top recess and form the mattress core with a continued upper surface of the mattress. The inserts are provided with at least two different firmness of the foam, preferably with three different firmness of the foam selected from firm, medium and soft, producing as such an inexpensive, novel consumer-adjustable mattress in which the consumer can change the firmness of the entire mattress and/or the firmness on either side of the bed to accommodate each sleeper and/or the firmness under certain “body zones” within the mattress for their own personalized comfort preference and to reduce tossing and turning.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present patent application is a continuation-in-part of U.S. patent application Ser. No. 15/461,207 entitled “Mattress and Topper with Variable Area Deflection Areas for Ultra-low Pressures with Postural Alignment”, filed at the U.S. Patent Office on Mar. 16, 2017 which claims the benefits of priority of U.S. Patent Applications No. 62/335,959, entitled “Mattress and Topper with Variable Area Deflection Means for Ultra-low Pressures with Postural Alignment”, and filed at the U.S. Patent Office on May 13, 2016, and No. 62/422,154, entitled “Mattress and Topper with Variable and Adjustable Area Deflection Means for Ultra-low Pressures with Postural Alignment”, and filed at the U.S. Patent Office on Nov. 15, 2016, the content of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention belongs to the field of mattresses and relates in particular to modifications of foam mattresses having an adjustable core for adjusting and customizing its firmness. The core comprises inserts having different firmness forming as such different deflective areas in the core of the mattress.

BACKGROUND OF THE INVENTION

It is known that the quality of sleep has a significant effect on the quality of life. Multiple clinical studies have correlated poor sleep quality with hypertension, obesity, stroke and diabetes. It is also known that mattresses can significantly affect sleep quality.

All existing consumer mattresses impart sleep-disturbing side-lying interface pressures to the body. Mattress-induced discomfort caused by excessive body pressures and postural misalignment result in increased tossing and turning causing sleep disruption and reduced sleep quality. An ideal mattress must have the support and resiliency over the length of the body to support the body in postural alignment while also providing ultra-low body pressures on all parts of the body in contact with the mattress to reduce mattress pressure-induced sleep disturbance.

The object of this invention is to eliminate mattress-induced sleep quality degradation. The present invention is the result of many years of university sleep research and development. The construction of over 100 prototypes was required to solve the heretofore unsolved equation of providing ultra-low pressures with optimal postural alignment.

Ultra-low mattress body interface pressure can be defined as at or below 0.6 PSI (32 mmHg), medically known as the ischemic pressure threshold. This interface pressure between the mattress and body allow the capillaries of the skin to remain open thereby greatly reducing or eliminating the incidence of pressure-induced sleep-disrupting movement. This pressure, if unrelieved, would eventually cause a decubitus ulcer (bed sore) to form.

Side sleeping is the most common and desired sleep position. Most existing consumer mattresses achieve back-lying body pressures on most, but not all parts of the body, of 0.6 PSI. If the back-lying area is about 900 square inches, that is usually sufficient area to maintain low pressures on most parts of the body. But the same side-lying body only presents about 500 square inches of contact area which, under the same load, significantly increases the unit area pressure to higher than 0.6 PSI on some parts of the body, notably the shoulder and hip areas, also known as bony prominences.

Achieving 0.6 psi or below on all body areas, including the shoulder and hip areas, when side-lying on static conventional mattresses—without certain mattress structural modifications—cannot be achieved with current materials. Prototypes leading to the present invention have achieved side-lying pressures on the shoulder and hip—as well as the rest of the body—of significantly less than 0.6 psi.

Since a recumbent body has both varying density and contour in the longitudinal direction, the ideal mattress must conform (deflect) to these variations in order to achieve correct postural alignment. The deflection parameters of the mattress must vary along its length to match the varying body density and contours while maintaining interface pressures at or below 0.6 PSI.

Few would agree that a single mattress firmness is comfortable for all users. What might be a medium firmness for one may feel too firm or too soft for another. That is why many mattress manufacturers provide mattresses with varying degrees of firmness, yet this strategy does not provide a differing firmness for each sleeper on the same bed. A firm mattress would be firm for both sleepers as would be a soft or medium firmness.

A select few mattress manufacturers have marketed mattresses in which the mattress cover can be unzipped to allow the customer to interchange certain internal components of the mattress which have a different firmness to suit a customer's comfort preference.

These consumer adjustments are usually horizontal full-size mattress layers of foam which can be rearranged vertically within the mattress, i.e. to obtain a softer or firmer top-sleep layer. Others are manufactured with other types of interchangeable components, but they are very expensive.

Another object of the invention is a means of producing an inexpensive, novel consumer-adjustable mattress in which the consumer can change the firmness of the entire mattress and/or the firmness on either side of the bed to accommodate each sleeper and/or the firmness under certain “body zones” within the mattress for their own personalized comfort preference and to reduce tossing and turning.

New foam mattresses and toppers by the inventor using foam deflection are disclosed in international application no. WO 2016/023109 A1 (Torbet) wherein the top portion of the mattresses comprises a plurality of displacement tunnels at different body part areas, such as shoulders or hip area, allowing the body part area foam above the tunnel to displace downward to provide pressure reduction and alignment for the body part such as shoulders or hip. Although the invention disclosed in this international application is pretty efficient, there is place for improvement in the shape, number and location of the channels for improving or modulating pressure reduction, alignment and comfort.

SUMMARY OF THE INVENTION

The shortcomings of the prior art are generally mitigated by new foam mattresses comprising deflective areas for reducing pressure reduction and alignment for the body parts in contact with the deflective areas.

The invention is directed to a foam mattress having an adjustable mattress core for adjusting and customizing a firmness of the mattress, the foam mattress comprising: a foam base having an upper surface defining a top recess; and a plurality of foam inserts each configured to be disposed and assembled into the top recess to fill the top recess and form the mattress core with a continued upper surface of the mattress,

wherein the inserts are provided with at least two different firmness of the foam.

The inserts having different firmness, they form different deflective areas in the core of the mattress.

According to another preferred embodiment, the inserts are provided according to three different firmness of the foam selected from firm, medium and soft. The firmness of a foam mattress is characterized by its Indentation Load Deflection or ILD. By “firm”, it is meant in the present application a foam having a ILD from 26 to 32. By “medium”, it is meant in the present application a foam having a ILD from 18 to 24. By “soft”, it is meant in the present application a foam having a ILD from 10 to 16. The density of the foam is preferably from 1.6 to 2.2 lb/CuFt.

According to another preferred embodiment, the foam mattress further comprises a pair of longitudinal foam side rails to be placed into the top recess each along one of one of the longitudinal edges of the base between a head section and a foot section of the mattress, the inserts being then configured to be placed into the top recess formed between the head and foot sections and the pair of lateral rails, wherein the foot section, the head section, the two longitudinal foam side rails and the inserts once in placed form the continued upper surface of the mattress.

According to another preferred embodiment, the foam base and the pair of longitudinal foam side rails may form a monoblock of foam.

According to another preferred embodiment, the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress.

According to another preferred embodiment, all the inserts of one side of the mattress have a different firmness than the inserts of the other side of the mattress.

According to another preferred embodiment, the inserts are affixed into the top recess using Velcro® bands. Other ways to fix the inserts and rails into the recess to form the core are possible without departing from the present invention.

According to another preferred embodiment, a lower surface of the foam base defines lateral grooves allowing the mattress to bend, such as to be used in a medical bed.

According to another preferred embodiment, the mattress may further comprise a foam topper configured to cover and match the upper surface of the mattress entrapping as such the inserts.

According to another preferred embodiment, a sealable cover configured to wrap the mattress and topper once assembled may be provided. Preferably, the sealable cover can be made of a flame retardant fabric.

The invention is also directed to a method for adjusting and customizing a firmness of a foam mattress, the method comprising the steps of:

-   -   i. providing a foam base having an upper surface defining a top         recess;     -   ii. providing a plurality of foam inserts each configured to be         disposed and assembled into the top recess, the inserts being         provided at least with two different firmness of the foam;     -   iii. selecting the inserts in accordance with the firmness         thereof; and     -   iv. disposing the selected inserts into the top recess until to         form a continued upper surface of the mattress.

According to a preferred embodiment, in step ii), the inserts are provided according to three different firmness of the foam selected from firm, medium and soft.

According to another preferred embodiment, the method may further comprise between steps ii) and iii) the steps of:

-   -   a) providing a pair of longitudinal foam side rails;     -   b) placing the rails into the top recess each along one of the         longitudinal edges of the base between a head section and a foot         section of the mattress, the inserts being then configured to be         placed in step iii) into the top recess formed between the head         and foot sections and the pair of lateral rails,     -   wherein the foot section, the head section, the two longitudinal         foam side rails and the inserts once in placed form the foam         mattress with a continued upper surface.

According to another preferred embodiment, the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress, the method further comprising the step of

-   -   v. selecting the inserts of one side of the mattress with a         different firmness than the inserts of the other side of the         mattress.

According to another preferred embodiment, the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress, the method further comprising the step of

-   -   vi. selecting the inserts of each column and/or row with a         different firmness to customized each side of the mattress.

According to another preferred embodiment, the method further comprises the step of entrapping the inserts forming the mattress core by placing a foam topper configured to cover and match the upper surface of the mattress.

According to another preferred embodiment, the method further comprises the step of wrapping the foam mattress with a sealable cover configured to wrap the mattress and topper once assembled.

The invention is yet directed to a kit for adjusting and customizing a firmness of a foam mattress, the kit comprising:

-   -   a foam base having an upper surface defining a top recess; and     -   a plurality of foam inserts each configured to be disposed and         assembled into the top recess to fill the top recess and form         the mattress core with a continued upper surface of the         mattress, wherein the inserts are provided with at least two         different firmness of the foam.

According to another preferred embodiment, the inserts are provided according to three different firmness of the foam selected from firm, medium and soft, the kit further comprising a manual of use for assisting a person to assemble the mattress and customize the firmness of the mattress.

The preferred embodiments disclosed herein above for the foam mattress or the method can be applied to the kit according to the invention.

The present invention is preferably achieved by CNC (Computer Numerical Control) cutting the structural modifications (channels, slots and voids) into the mattress foam which support each area of the body.

Other and further aspects and advantages of the present invention will be obvious upon an understanding of the illustrative embodiments about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawings in which:

FIG. 1 is a schematic perspective view in cross-section of the core of the mattress in accordance with a first embodiment of the invention;

FIG. 2 is an exploded schematic front elevation view in cross-section of the core of the mattress in accordance with a first embodiment of the invention;

FIG. 3 depicts the first embodiment of FIGS. 1 and 2 with body area displacement modifications;

FIG. 4 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a second embodiment of the invention;

FIG. 5 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a third embodiment of the invention;

FIG. 6 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a fourth embodiment of the invention;

FIG. 7 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a fifth embodiment of the invention;

FIG. 8 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a sixth embodiment of the invention;

FIG. 9 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a seventh embodiment of the invention;

FIG. 10 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a eighth embodiment of the invention;

FIG. 11 is a schematic front elevation view in cross-section of the core of the mattress in accordance with a ninth embodiment of the invention;

FIG. 12 is a schematic perspective view in cross-section of the core of the mattress in accordance with the first embodiment of the invention (FIG. 1);

FIG. 13 is a schematic perspective view in cross-section of the core of the mattress in accordance with the first embodiment of the invention (FIG. 1 or 12) without side-lying body contact;

FIG. 14 is a schematic perspective view in cross-section of the core of the mattress in accordance with the first embodiment of the invention (FIG. 1 or 12) with side-lying body contact;

FIG. 15 depicts the shoulder area of the first embodiment without contact;

FIG. 16 depicts the shoulder area of the first embodiment with contact;

FIG. 17 depicts the first embodiment of FIG. 1 without back-lying body contact;

FIG. 18 depicts the first embodiment of FIG. 1 with back-lying body contact;

FIG. 19 is a schematic perspective view in cross-section of the core of the mattress with body area displacement modifications in accordance with a tenth embodiment of the invention;

FIG. 20 is a schematic front elevation view in cross-section of the core of the mattress with body area displacement modifications in accordance with a tenth embodiment of the invention;

FIG. 21 is a schematic perspective view in cross-section of a topper with body area displacement modifications in accordance with a eleventh embodiment of the invention;

FIG. 22 is a schematic front elevation view in cross-section of the core of the topper of FIG. 21;

FIG. 23 is a schematic front elevation view in cross-section of a mattress in accordance with a twelfth embodiment of the invention

FIG. 24 is a schematic front elevation view in cross-section of the core of the mattress of

FIG. 23 and a topper, including dimensions;

FIG. 25 shows a topper including an enhancer according to a preferred embodiment of the invention;

FIG. 26 shows toppers including full-length enhancers according to different preferred embodiments of the invention;

FIG. 27 shows a topper including half-length enhancers according to preferred embodiments of the invention;

FIG. 28 compares a mattress of the prior art with a mattress in accordance with a preferred embodiment of the invention;

FIG. 29 illustrates different slots or channels in the mattress in accordance with four preferred embodiments of the invention; and

FIG. 30 illustrates the difference of deflection between a regular topper or mattress with no slots (left) with a topper or mattress with slots in accordance with a preferred embodiment of the invention;

FIG. 31 illustrates the different elements or sections of a mattress having interchangeable inserts in accordance with another preferred embodiment of the invention;

FIG. 32 illustrates a mattress having 18 interchangeable inserts in accordance with the other preferred embodiment of the invention;

FIG. 33 illustrates a mattress having 8 interchangeable inserts in accordance with the other preferred embodiment of the invention;

FIG. 34 illustrates a mattress having 6 interchangeable inserts in accordance with the other preferred embodiment of the invention;

FIG. 35 illustrates a mattress having 8 interchangeable inserts and how to insert one of the inserts in accordance with the other preferred embodiment of the invention;

FIG. 36 illustrates a mattress having 8 interchangeable inserts and how to place a topper, in accordance with the other preferred embodiment of the invention;

FIG. 37 illustrates mattresses having each 8 interchangeable inserts and their relation with a body laid on the mattress for different body heights, in accordance with the other preferred embodiment of the invention;

FIG. 38 illustrates a mattress having 8 interchangeable inserts with one side having firm insert and the other side having soft, in accordance with the other preferred embodiment of the invention;

FIG. 39 illustrates a mattress having 8 interchangeable inserts with each side having customized insert firmness, in accordance with the other preferred embodiment of the invention;

FIG. 40 illustrates a mattress having 8 interchangeable inserts with no lateral rails to form the core, in accordance with the other preferred embodiment of the invention; and

FIG. 41 illustrates a foam base of a mattress where the head section, the foot section and the lateral rails are fused to form a monoblock, in accordance with the other preferred embodiment of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A novel mattress and/or topper will be described hereinafter. Although the invention is described in terms of specific illustrative embodiments, it is to be understood that the embodiments described herein are by way of example only and that the scope of the invention is not intended to be limited thereby.

All mattress and toppers embodiments shown are preferably bi-directional, meaning that the head end and foot end of the mattress are identical and symmetrical. This allows the mattress or topper to be placed on the bed foundation in either direction without affecting sleep performance. Of course, the present invention cannot be limited to bi-directional mattresses and toppers.

FIGS. 1 and 2 shows a first mattress base core in accordance with a first embodiment of the invention. The mattress is formed of two foam sections with a top section 1 adapted to be affixed on a bottom base or core section 2. The base core section can be a 8″ base piece. The two sections can be glued but other methods known in the art can be used to assemble the two sections together.

Mattress Deflection Areas

The core section 2 comprises various specific load deflection areas 20-50 which correspond to different recumbent body areas to reduce pressures to those areas while maintaining postural alignment. The areas are preferably CNC contour cut to create transversal longitudinal channels that can be either slots 3, grooves 4 or void 5.

The shoulder area 20 may comprise a series of slots 3, preferably parallel slots, for providing pressure reduction and shoulder deflection for postural alignment. A V-groove 4 can be placed between the torso area 30 and the pelvic area 40 to provide pelvic deflection. The void 5 is placed at the longitudinal mattress center to provide pressure reduction for the greater trochanter.

FIG. 3 better identifies each of the deflection-modified body areas: head area 10, shoulder area 20, torso area 30, pelvic area 40 and trochanter area 50 with examples of general lengths for each area. Since the mattress core in this example is bi-directional in placement orientation and deflection parameters, both areas 10, 20, 30 and 40 are identical in support and deflection.

High side-lying trochanter pressure exists in all current mattresses and is the most common cause of mattress-induced sleep disruption. The hip area is comprised of both areas 40 and area 50. Both areas 40, one supporting the pelvis and the other supporting the upper thigh, act together to redistribute and relieve the high pressure which would otherwise be placed on the greater trochanter. Area 50 further reduces trochanteric pressure. Likewise, the torso area 30 reduces pressure on the shoulder area 2.

Different Form of Channels

FIGS. 4 to 11 illustrate different configurations and forms of the channels present in the mattress or topper in accordance with different preferred embodiments. While referring to the shoulder are in the following description, the same description of the slots may apply for the lower body area when the mattress is symmetrical.

FIG. 4 shows an embodiment where the trochanter area comprises a void 54 deeper than the void visible on FIG. 1 or 2, to reduce the possibility of trochanter contact with the bottom of the void.

FIG. 5 shows an embodiment with four inverted shoulder slots 15 which are narrower at the top than at the bottom of the slot.

FIG. 6 shows an embodiment with four inverted shoulder slots 16 having a drop-like shape closed at the top and in full contact with the top layer. FIG. 7 shows an embodiment with five inverted shoulder slots 17 instead of four slots as in FIG. 6, to further decrease shoulder pressure.

FIGS. 8 and 9 show embodiments where the four shoulder slots, while presenting the same shape has different depths. As illustrated, the two external slots 28 or 29 are deeper than the two internal slots 18 or 19. The deeper slots allow greater deflection of the entire shoulder area 20.

FIGS. 10 and 11 show embodiments as above where the four shoulder slots, while presenting the same drop-like shape has different depths. In FIG. 10, there are two smaller internal slots 110 whereas in FIG. 11, there are three internal sluts 111, in both case having two deeper external slots.

Foam Deflection and Body Alignment

FIG. 12 identical to FIG. 1 shows the first mattress core embodiment in perspective view for reference.

FIG. 13 shows the first mattress core embodiment without side-lying body compression. Shoulder support elements 3 are shown uncompressed. The trochanter void 5 is shown uncompressed. FIG. 14 shows the first mattress core embodiment with side-lying body compression. The slots are shown under various degrees of compression. The trochanter void 5 is shown compressed. The trochanter void 5 under compression allows the angled sides of the void to deflect, dramatically reducing pressure on the trochanter body area.

FIG. 15 details the shoulder area 20 uncompressed with the shoulder slots 21-24 in their as-cut relaxed positions. FIG. 16 details the shoulder area compressed. During shoulder compression, the shoulder support elements 20 compress independently. The shoulder slots 21, 22, 23 and 24 under compression expand horizontally to reduce the lateral foam tensile forces which would otherwise occur if the shoulder slots were not there to release the tensile forces. This lateral foam tensile force, if unrelieved, would dramatically increase the unit area pressure on the shoulder.

FIG. 17 shows the first mattress core embodiment without back-lying body compression. The slots 3 and mattress areas are shown uncompressed. The trochanter void 5 is also shown uncompressed. FIG. 18 shows the mattress with back-lying body compression. The shoulder support slots 3 are shown under various degrees of compression. The trochanter void 5 is also compressed. The trochanter void 5 under compression allows the angled sides of the void to deflect, allowing the buttocks area to deflect into the mattress. The deflection in this area creates significant additional support in the lumbar area when back-lying as well as allowing increased knee flexion which helps reduce low-back pain.

Additional Embodiments

FIGS. 19 & 20 show another mattress embodiment comprised of a top foam layer 6 and a bottom foam layer 7. The four identical slots 8 extend from the upper surface through the mattress which eliminates the horizontal tensile forces present in the top foam layer 6 as shown in embodiments 1-9. This embodiment is comprised of nine specialized deflection areas: head area 10, shoulder area 20, torso area 30, pelvic area 40 and trochanter area 50. Since the mattress core is bi-directional in both placement orientation and deflection parameters, both areas 40 are identical in support and deflection. The hip area is comprised of both areas 40 and area 50. Both areas 40, one supporting the pelvis and the other supporting the upper thigh, act together to redistribute and relieve the high pressure which would otherwise be placed on the greater trochanter.

The shoulder or lower body area 20 also comprise a lateral slot 25 located between two slots 8, and two channels 26 extending from the lower surface of the mattress. The different slots 8, 25 and channels 26 collaborate for modifying the deflection of the foam under the body. The lower channels 26 can be used also for modulating such deflection by inserting inserts made of the same foam, as detailed herein below.

FIGS. 21 and 22 show a CNC cut foam mattress topper embodiment 200. As with all mattress embodiments, the topper is comprised of nine specialized deflection areas: head area 10, shoulder area 20, torso area 30, pelvic area 40 and trochanter area 50. The deflection channels 60 if the shoulder or low body area 20 provide shoulder elevation drop which reduces shoulder pressure by redistributing some of that pressure to the torso area 30. Torso/pelvic V-grooves 70, delimiting the torso and pelvic areas 30, 40 allows the heavier hip areas 40, 50 to deflect more than the adjacent torso area. The trochanter channel 80 extending from the lower surface reduces pressure on the greater trochanter 50.

FIGS. 23 and 24 illustrate another embodiment of the mattress 230 comprising at least one internal lateral channel 231 operatively extending between two of said first lateral channels 232 inside the mattress. In the example illustrated on FIGS. 23 and 24, the foam mattress 230 comprises one internal lateral channel 231 between two of said first lateral channels 232, each internal lateral channel having preferably an ovoid cross-section. The ovoid channels 231 can be formed by cutting and removing the channel plugs through the top cuts 233. The ovoid channels 231 allow reducing shoulder pressure more than the vertically slotted shoulder area 232 without them. As illustrated on FIG. 24, the mattress 230 can be covered by a laminate or topper 234 before being wrapped in a zipped sleep cover 235 or the like.

Mattresses or Toppers with Modulating Inserts

Referring to FIG. 25, it is shown a perspective view of the mattress topper/enhancer 200 oriented as if lying on a mattress, with the flat area being the top 210 of the topper/enhancer. The zippered cover has been removed for clarity. Full width topper/enhancer insert 300 can be placed into the central channel 60 of the shoulder area 20 of the topper/enhancer. The insert is preferably a foam piece which has been contour cut to form the shoulder channel 60 and would otherwise be discarded if not used as the insert 300. Once the insert(s) have been placed in the channel(s) the zippered cover would be closed to maintain the topper and insert(s) all together.

Referring to FIG. 26, it is shown an insert placed into one channel (A), two channels (B) or three channels (C) as decided by the user's comfort preference. These inserts in this case are along the full width of the topper/enhancer 300 or a half-length inserts 310 that can be placed on one side only of the topper/enhancer. This would typically apply to a two-person-sized topper/enhancer like a Full, Queen or King sized bed, allowing each sleeper to customize the shoulder comfort on their side to his/her preference. FIG. 27 shows different examples of the many combinations of insert placements possible for individual customized comfort using half-length inserts 301.

There are many ways a sleeper can vary the firmness:

a. nothing in the slots (see FIG. 22A);

b. one insert 310 in the central slot 60 (see FIG. 24A); or into slot 61 or into slot 62;

c. two inserts 310 in the central slot 60 and slot 61 (see FIG. 22B); the central slot 60 and slot 62; or the slots 61 and 62; or

d. three inserts in slots 60, 61 and 62 on one side of the bed (FIG. 24C) or the other side (FIG. 24D).

There are several advantages of the use of inserts/enhancers. First, the enhancers can be made from the cut-out of the foam mattress when cutting the channels reducing foam waste. Second, the use of the enhancers allows precisely and easily customizing the user's sleeping comfort, one side of the bed or both sides.

Methods

The present invention also concerns a method for customizing the comfort of a mattress, comprising at least the steps of:

-   -   a) providing a mattress or a topper as disclosed herein with the         plurality of slots and/or voids cut into the foam for supporting         each area of the person body in a specific way to control         postural alignment while providing ultra-low mattress-body         interface pressures for all body areas regardless of recumbent         position;     -   b) providing cut-outs of foam obtained during the manufacturing         of the mattress or topper when making the slots and/or voids;         and     -   c) reinserting one or several cut-outs in the slots and/or voids         at least along a section of the slots and/or voids for         customizing or adjusting the postural alignment.

Referring to FIG. 28, the deflection areas of the top mattress section of the prior art: WO 2016/023109, may be prone to several deficiencies:

-   -   1. The depth of the foam above the shoulder “tunnel” is limited         which allows the firmer base foam (darker) to feel more         prominent in that area than desired.     -   2. The height to width ratio of the shoulder “tunnel” tends to         allow a permanent non-recoverable body impression in that area         under heavier loads.     -   3. The vertical deflection capability of the shoulder area is         less than desired.     -   4. Since the top mattress section requires a 3″ height to         perform, and the desired overall height is 10″, the base foam         must be 7″ which is marginal in preventing “bottoming out”, or         approaching a terminal firmness which can defeat the ultra-low         pressure parameter.

Still referring to FIG. 28, the mattress of the present invention may solve the above-mentioned deficiencies of the prior art:

-   -   1. The vertical tapered slots in the shoulder area provide         Indention/Force/Deflection (IFD) reduction of the foam to         prevent the firmer feel of an un-modified shoulder area.     -   2. The top mattress section is supported by the un-slotted         (land) areas of the base foam, preventing any significant body         impressions to form.     -   3. The slotted shoulder area provides both the IFD reduction and         deflection desired for both back and side-lying comfort.     -   4. The support provided by the slotted shoulder area allows an         8″ base foam which prevents “bottoming out”.     -   5. Moreover, the slotted design allows greater flexibility to         fine tune future support and firmness parameters.

How slot and void size/shape/placement affect foam support, firmness and deflection:

-   -   1. Un-slotted foam has the most support and firmness and most         resistance to deflection.     -   2. The width of a given vertical slot in relation to the width         of the adjacent un-slotted foam determines the IFD reduction of         the foam (softening).     -   3. The depth of a given vertical slot determines the depth to         which the IFD reduction (softening) acts.     -   4. A vertical slot releases the horizontal tensile forces         inherent in un-slotted foam.     -   5. A vertical slot creates an “edge effect” whereby the foam IFD         is lower near the foam edge than the foam middle.

6. A void's shape determines the adjacent foam's compression characteristics.

Referring to FIG. 29, pic A, the foam adjacent to the top of the slot will compress more easily than at the bottom. Tensile release occurs to the lowest point of the slot. The cross sectional area of the slot relative to the adjacent cross sectional foam area determines the IFD reduction.

Referring to FIG. 29, pic B, the foam adjacent to the bottom of the slot will compress more easily than at the top. Tensile release occurs to the lowest point of the slot. The cross sectional area of the slot relative to the adjacent cross sectional foam area determines the IFD reduction.

Referring to FIG. 29, pic C, the foam adjacent to the “arrowhead” area will compress more easily than the foam adjacent to the “arrow stem”. With a larger arrowhead void area than either pic A or B at the same depth, it will compress more easily at the same depth under the same load. Tensile release occurs to the lowest point of the void. The cross sectional area of the void relative to the adjacent cross sectional foam area determines the IFD reduction.

Referring to FIG. 29, pic D, the void is similar to the arrowhead of pic C. But with smaller arrowhead angles, the adjacent foam will compress more easily under the same load.

Tensile release occurs to the lowest point of the void. The cross sectional area of the void relative to the adjacent cross sectional foam area determines the IFD reduction.

FIG. 30 illustrates how foam without slots or voids (left) compares to foam with tensile release slots (right). Even though polyurethane and other flexible foams have a very low Young's modulus, tensile release dramatically reduces the foam tensile forces which act to restrict compression. The result is greater deflection and greater contact area. Greater contact area equates to lower pressure per unit area, which can be extremely important in the present application.

The flexibility to control both area deflection and mattress/body interface pressures by slot or void size, depth, shape and placement comprises a new and better way to manufacture mattresses and toppers. No other mattress or topper manufacturing process has this ability to fine tune and control comfort parameters, whether based on consumer preferences or other decision factors.

Indentation force-deflection (IFD) is a process used in the flexible foam manufacturing industry to assess the “softness” of a sample of foam such as memory foam. To conduct an IFD test, a circular flat indenter with a surface area of 323 square centimeters (50 sq. inches—8″ in diameter) is pressed against a foam sample usually 100 mm thick and with an area of 500 mm by 500 mm (ASTM standard D3574). The foam sample is first placed on a flat table perforated with holes to allow the passage of air. It is then “warmed up” by being compressed twice to 75% “strain”, and then allowed to recover for six minutes. The force is measured 60 seconds after achieving 25% indentation with the indenter. Lower scores correspond with less firmness; higher scores with greater firmness. U.S. measurements are given in pounds-force, and European ones are given in Newton (N).

In the mattress case, the top 2″ foam layer would typically be 19-21 IFD. The 8″ base layer would typically be 25-27 IFD. Firmer or softer IFD's can be used, but quickly exit the “comfort zone” for most people. The topper would typically be 19-21 IFD. (see IFD definition below).

The foam used for the making of the mattresses or toppers disclosed herein are selected from the foams generally used in the art of making foam mattress or toppers. For instance, the foam may comprise flexible polyurethane (including modified polyurethanes such as visco-elastic PE foam), latex or any other type of flexible foam.

Matresses with Interchangeable Inserts

As illustrated from FIGS. 31 to 41, the invention as claimed is a foam mattress 400 having an adjustable mattress core 405 for adjusting and customizing a firmness of the mattress, the foam mattress comprises a foam base 410 having an upper surface defining a top recess 415; and a plurality of foam inserts 430 each configured to be disposed and assembled into the top recess to fill the top recess and form the mattress core with a continued upper surface of the mattress (See FIG. 31C for example). The inserts are provided with at least two different firmness of the foam.

The inserts are provided according to three different firmness of the foam selected from firm, medium and soft. The firmness of a foam mattress is characterized by its Indentation Load Deflection or ILD. By “firm”, it is meant in the present application a foam having an ILD from 26 to 32. By “medium”, it is meant in the present application a foam having an ILD from 18 to 24. By “soft”, it is meant in the present application a foam having an ILD from 10 to 16. The density of the foam is preferably from 1.6 to 2.2 lb/CuFt.

FIG. 40 shows a foam mattress according to the invention with the core formed only of the inserts placed in the recess. As illustrated in the other Figures, the foam mattress may further comprise a pair of longitudinal foam side rails 420 to be placed into the top recess 415 each along one of one of the longitudinal edges of the base 410 between a head section 411 and a foot section 412 of the mattress, the inserts being then configured to be placed into the top recess formed between the head and foot sections and the pair of lateral rails, wherein the foot section, the head section, the two longitudinal foam side rails and the inserts once in placed form the continued upper surface of the mattress 435.

FIG. 31 shows the various foam components of the adjustable mattress core (queen/king size shown) 400. All components, after assembly, will be inserted into a preferably flame retardant zippered mattress cover (not shown).

FIG. 31A shows a foam mattress base 410 which has been preferably contour cut as shown to receive the other components. The top recess is typically 2.5″-3″ deep.

FIG. 31B shows the addition, preferably by adhesive, of two side rails 420 laterally spaced on either side of the base 410. The side rails are preferably secondarily cut from the piece removed from the recess of the base to provide adequate edge support for sitting. Other ways of making can be considered. The side rails are typically 2.5″-3″ high by 4″-5″ wide. The Base and the sides rails can alternatively form a unique peace of foam.

FIG. 31C shows the addition of the foam inserts 430 of the first embodiment which are preferably loose-laid, interchangeable and removable from the base recess. Each side of the mattress shown has its own set of inserts. The foam inserts are typically 2.5″-3″ thick.

FIG. 31D shows the addition of the top comfort layer 440 prior to placement over the base with side rails and inserts in place. The top comfort layer is typically 2″ thick.

FIG. 32 shows a detail of the previous embodiment 400 with interchangeable inserts 430 installed. If all firm, all medium or all soft firmness inserts are desired, this embodiment (showing a queen or king size core), preferably requires 18 inserts of firm foam, 18 inserts of medium firmness foam or 18 inserts of soft foam, 9 for each side of the mattress. If it is a twin, twin long mattress, it would require 9 inserts for each firmness. If a consumer desires a firmness other than the 3 provided it would require an additional 9 or 18 inserts per firmness, depending on mattress size. The lower surface of the foam base may define lateral grooves 413 allowing the mattress to bend, for example to be used in a medical bed.

FIG. 33 shows another embodiment with interchangeable inserts installed. If all firm, all medium or all soft firmness inserts are desired, this embodiment (showing a queen or king size core), requires 8 inserts of firm foam, 8 inserts of medium firmness foam and 8 inserts of soft foam, 4 for each side of the mattress. If it is a twin, twin long mattress, it would require 4 inserts each firmness

If a consumer desires a firmness other than the three provided it would require an additional 4 or 8 inserts per firmness, depending on mattress size.

FIG. 34 shows a third embodiment with interchangeable inserts installed. If all firm, all medium or all soft firmness inserts are desired, this embodiment (showing a queen or king size core), requires 6 inserts of firm foam, 6 inserts of medium firmness foam and 6 inserts of soft foam, 3 for each side of the mattress. If it is a twin, twin long mattress, it would require 3 inserts each firmness.

If a consumer desires a firmness other than the 3 provided it would require an additional 3 or 6 inserts per firmness, depending on mattress size.

FIG. 35 shows an example of an interchangeable insert of the second embodiment as it would fit into the recess of the base with adjacent inserts in place.

FIG. 36 shows the top foam layer in position ready for loose (non-adhered) placement over the base, side rails and inserts prior to cover closure.

FIG. 37 shows the size of a 4′11″, 5′6″ and 6′ body in relation to a mattress core (without side rails for clarity) of the second embodiment to illustrate the mattress zone to body zone relativity. As an example, the shoulder insert longitudinal length should accommodate the shoulders of the three body lengths for any size mattress.

FIG. 38 shows a mattress 400 having one side comprising only firm inserts whereas the other side comprises only soft inserts.

FIG. 39 shows a mattress 400 where on each side of the bed, the customer can customized the firmness of the inserts 430 between firm, medium and soft, and as such providing different body alignment and comfort.

FIG. 40 illustrates a mattress 400 having 8 interchangeable inserts but no lateral rails to form the core.

FIG. 41 illustrates a foam base 410 of a mattress where the head section 411, the foot section 412 and the lateral rails 420 are fused to form a mono-block, in accordance with the other preferred embodiment of the invention. In FIG. 41, the base is symmetrical in that the head and foot sections are interchangeable.

While illustrative and presently preferred embodiments of the invention have been described in detail hereinabove, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art. 

What is claimed is:
 1. A foam mattress having an adjustable mattress core for adjusting and customizing a firmness of the mattress, the foam mattress comprising: a foam base having an upper surface defining a top recess; and a plurality of foam inserts each configured to be disposed and assembled into the top recess to fill the top recess and form the mattress core with a continued upper surface of the mattress, wherein the inserts are provided with at least two different firmness of the foam.
 2. The foam mattress of claim 1, wherein the inserts are provided according to three different firmness of the foam selected from firm, medium and soft.
 3. The foam mattress of claim 1, further comprising a pair of longitudinal foam side rails to be placed into the top recess each along one of one of the longitudinal edges of the base between a head section and a foot section of the mattress, the inserts being then configured to be placed into the top recess formed between the head and foot sections and the pair of lateral rails, wherein the foot section, the head section, the two longitudinal foam side rails and the inserts once in placed form the continued upper surface of the mattress.
 4. The foam mattress of claim 3, wherein the foam base and the pair of longitudinal foam side rails form a monoblock of foam.
 5. The foam mattress of claim 1, wherein the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress.
 6. The foam mattress of claim 3, wherein whole the inserts of one side of the mattress have a different firmness than the inserts of the other side of the mattress.
 7. The foam mattress of claim 1, wherein the inserts are affixed into the top recess using Velcro® bands.
 8. The foam mattress of claim 1, wherein a lower surface of the foam base defines lateral grooves allowing the mattress to bend.
 9. The foam mattress of claim 1, further comprising a foam topper configured to cover and match the upper surface of the mattress entrapping as such the inserts.
 10. The foam mattress of claim 9, further comprising a sealable cover configured to wrap the mattress and topper once assembled.
 11. The foam mattress of claim 10, wherein the sealable cover is made of a flame retardant fabric.
 12. A method for adjusting and customizing a firmness of a foam mattress, the method comprising the steps of: i. providing a foam base having an upper surface defining a top recess; ii. providing a plurality of foam inserts each configured to be disposed and assembled into the top recess, the inserts being provided at least with two different firmness of the foam; iii. selecting the inserts in accordance with the firmness thereof; and iv. disposing the selected inserts into the top recess until to form a continued upper surface of the mattress.
 13. The method of claim 12, wherein in step ii) the inserts are provided according to three different firmness of the foam selected from firm, medium and soft.
 14. The method of claim 12, further comprising between steps ii) and iii) the steps of: a) providing a pair of longitudinal foam side rails; b) placing the rails into the top recess each along one of the longitudinal edges of the base between a head section and a foot section of the mattress, the inserts being then configured to be placed in step iii) into the top recess formed between the head and foot sections and the pair of lateral rails, wherein the foot section, the head section, the two longitudinal foam side rails and the inserts once in placed form the foam mattress with a continued upper surface.
 15. The method of claim 12, wherein the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress, the method further comprising the step of v. selecting the inserts of one side of the mattress with a different firmness than the inserts of the other side of the mattress.
 16. The method of claim 12, wherein the inserts form two longitudinal columns and a plurality of rows of inserts; each column of insert corresponding to one lateral side of the mattress, the method further comprising the step of vi. selecting the inserts of each column and/or row with a different firmness to customized each side of the mattress.
 17. The method of claim 12, further comprising the step of entrapping the inserts forming the mattress core by placing a foam topper configured to cover and match the upper surface of the mattress.
 18. The method of claim 17, further comprising the step of wrapping the foam mattress with a sealable cover configured to wrap the mattress and topper once assembled.
 19. A kit for adjusting and customizing a firmness of a foam mattress, the kit comprising: a foam base having an upper surface defining a top recess; and a plurality of foam inserts each configured to be disposed and assembled into the top recess to fill the top recess and form the mattress core with a continued upper surface of the mattress, wherein the inserts are provided with at least two different firmness of the foam.
 20. The kit of claim 19, wherein the inserts are provided according to three different firmness of the foam selected from firm, medium and soft, the kit further comprising a manual of use for assisting a person to assemble the mattress and customize the firmness of the mattress. 